Tub Water Supply Line Buying Guide


Heavy-Duty Freestanding Tub Water Supply Line with Shutoff Valves in Polished Brass, 57" Erica Cast Iron Clawfoot Tub Heavy-Duty Freestanding Tub Water Supply Line with Shutoff Valves in Polished Brass, 57" Erica Cast Iron Clawfoot Tub

Choosing the right water supply line is an essential step in getting your bathtub set up. With a few key factors to consider in choosing the right type of water supply line, the decision can be quite tedious without the proper knowledge. Follow along to learn about the various supply line types and when to use them, ensuring this part of the process is as seamless as possible.

Be sure to follow any local codes or ordinances, and when in doubt, consult a local professional when deciding which supply lines to select.

Why Do I Need a Water Supply Line?


Directing your water source to your tub faucet, water supply lines ultimately bring functionality to your bathtub. You’ll have two supply lines: one coming directly from your water line for cold water, and the other from your water heater for hot water.

Serving as your water connector, the key factors in determining the appropriate water supply lines are the location and measurements of your water supply’s rough-in and your tub faucet configuration.

Heavy-Duty Freestanding Tub Supply Line & Freestanding Telephone Tub Faucet in Chrome

Types of Tub Water Supply Lines

Sometimes referred to as clawfoot tub supply lines, tub water supply lines are generally compatible with any style of tub. Learn more about each type below.

Braided water supply line

Braided Supply Lines

When using braided supply lines rather than one of the types of decorative lines listed above, tub supply couplings, or bathcock couplings, are required. You might use braided supply lines for two reasons:

(1) Your tub and faucet are up against a wall, so your supply lines are hidden, or

(2) Your water supply is coming from the wall instead of the floor (as with the previous options).

Braided supply lines will not fit your tub-mount faucet alone, so these couplings are necessary to attach the lines to your faucet.

Heavy Duty Freestanding Tub Water Supply Line in Oil Rubbed Bronze

Freestanding Supply Lines

Freestanding supply lines are used with tubs that have no faucet drillings. They are made from heavy duty brass tubing designed to support the weight of the tub faucet. The freestanding tub supplies must be securely anchored to the floor of the home, with some also requiring wall supports.

While most applications will use 7" centers, they are roughed-in according to the spread of the faucet.

Double Offset Tub Water Supply Line with Cross Handle Valves

Double Offset Supply Lines

Double offset supply lines are used with wall-mount faucets with 3-3/8" centers. This supply tubing features two bends at the top, sloping slightly outward from the tub faucet.

At the floor, the plumbing for double offset supplies should be roughed in at 8" on centers.

Deck-Mount Straight Supply Line With Cross-Handle Stops for Threaded Pipe

Straight Supply Lines

Straight supply lines are used for deck or rim-mount faucets. These supply lines are aligned with the tub faucet holes.

For a tub faucet with 7" centers, the supply lines would be roughed-in at 7" on centers in the floor.

Braided water supply line

Braided Supply Lines

When using braided supply lines rather than one of the types of decorative lines listed above, tub supply couplings, or bathcock couplings, are required. You might use braided supply lines for two reasons:

(1) Your tub and faucet are up against a wall, so your supply lines are hidden, or

(2) Your water supply is coming from the wall instead of the floor (as with the previous options).

Braided supply lines will not fit your tub-mount faucet alone, so these couplings are necessary to attach the lines to your faucet.

Heavy Duty Freestanding Tub Water Supply Line in Oil Rubbed Bronze

Freestanding Supply Lines

Freestanding supply lines are used with tubs that have no faucet drillings. They are made from heavy duty brass tubing designed to support the weight of the tub faucet. The freestanding tub supplies must be securely anchored to the floor of the home, with some also requiring wall supports.

While most applications will use 7" centers, they are roughed-in according to the spread of the faucet.

Double Offset Tub Water Supply Line with Cross Handle Valves

Double Offset Supply Lines

Double offset supply lines are used with wall-mount faucets with 3-3/8" centers. This supply tubing features two bends at the top, sloping slightly outward from the tub faucet.

At the floor, the plumbing for double offset supplies should be roughed in at 8" on centers.

Deck-Mount Straight Supply Line With Cross-Handle Stops for Threaded Pipe

Straight Supply Lines

Straight supply lines are used for deck or rim-mount faucets. These supply lines are aligned with the tub faucet holes.

For a tub faucet with 7" centers, the supply lines would be roughed-in at 7" on centers in the floor.

Installation Tips

  • All supply lines should be installed by a qualified, licensed plumber. We suggest that rough-in work is carried out with the tub on site to avoid costly mistakes.

  • Avoid over-tightening all connections. Snug the nuts by hand. Using a box wrench, tighten 1/4 turn. Check for leaks. Tighten 1/8 of a turn until leaks stop. Cast brass is one of the best materials known for plumbing pipes and valves, but it will crack or split if over-tightened.

  • Use Teflon tape on supply line threads instead of plumber's putty for the best water-tight seal.

Customization


As all floor-connected supply lines are on full display, you can find these available in a variety of eye-catching, rust-resistant finishes to best complement your tub and other surrounding fixtures. Common finishes include: Chrome, Oil-Rubbed Bronze, Brushed Nickel, Polished Brass, and Polished Nickel.

Freestanding Telephone Tub Faucet with Water Supple Line in Oil Rubbed Bronze
Chrome
Oil Rubbed Bronze
Brushed Nickel
Polished Brass
Polished Nickel

Additional Water Supply Line Information

Shutoff Valves: Tub supply lines are available with or without shutoff valves that allow you to shut the water off at the tub in the event of a water leak.

Supply Line Length: Decorative supply lines (except freestanding lines) can be easily cut with a tubing cutter to the correct length for installation.

Unusual Rough-In Centers: Supply lines made from high quality cast brass cannot be bent to vary the spread at the floor. If you have plumbing roughed in on unusual centers, it is suggested to either change the plumbing rough-in or use tub ells with braided water lines.

How Often To Replace: While it is recommended that most supply line hoses be replaced every 5 years to protect your home against potential leaks, braided supply lines can be replaced every 10 years due to their rubber core.

Shutoff Valves: Tub supply lines are available with or without shutoff valves that allow you to shut the water off at the tub in the event of a water leak.

Supply Line Length: Decorative supply lines (except freestanding lines) can be easily cut with a tubing cutter to the correct length for installation.

Unusual Rough-In Centers: Supply lines made from high quality cast brass cannot be bent to vary the spread at the floor. If you have plumbing roughed in on unusual centers, it is suggested to either change the plumbing rough-in or use tub ells with braided water lines.

How Often To Replace: While it is recommended that most supply line hoses be replaced every 5 years to protect your home against potential leaks, braided supply lines can be replaced every 10 years due to their rubber core.

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